Background: Intensified Prolonged Exposure (iPE) therapy has proven its efficacy in reducing PTSD symptoms. However, its effectiveness in naturalistic settings and underlying mechanisms of action...Show moreBackground: Intensified Prolonged Exposure (iPE) therapy has proven its efficacy in reducing PTSD symptoms. However, its effectiveness in naturalistic settings and underlying mechanisms of action are still under investigation. Objective: The current study investigates the effectiveness of iPE in reducing PTSD symptoms in a naturalistic setting. Additionally, the role of trauma-related maladaptive cognitions in predicting changes in PTSD symptoms was examined, thereby testing the cognitive model of PTSD. Methods: The study is based on anonymous data provided by the LUBEC mental health care facility in Leiden, following the iPE procedure outlined by Oprel et al. (2017). Patients with PTSD received 12 sessions of iPE administered over four weeks and two booster sessions at one-month intervals. Assessment of PTSD symptoms, including maladaptive cognitions, was conducted using the PCL-5 questionnaire at eight measurement time points: before the beginning of the treatment (baseline), during each of the four weeks of active treatment, after the two monthly booster sessions, and three months after the end of the treatment (end evaluation). Results: data of 58 participants was included in the study. The treatment resulted in a large improvement in PTSD symptoms, with 43.1% of the patients showing a clinically significant change in symptoms. Maladaptive trauma-related cognitions significantly decreased throughout the course of treatment. In contrast with expectations, preceding changes in maladaptive cognitions did not predict changes in PCL-5 score, while preceding changes in PCL-5 score predicted later changes in maladaptive cognitions. Conclusion: iPE is effective in reducing PTSD symptoms and maladaptive cognitions in a naturalistic setting. Preceding decrease in PTSD symptoms predicts a decrease in trauma-related cognitions; conversely, changes in cognitions do not impact later PTSD symptoms severity.Show less
